The present invention relates to shaped charge warheads and, in particular, to methods for controlling the shape and/or velocity distribution of particles in a jet produced by a collapsing liner in a shaped charge warhead.
In the prior art, for example, in U.S. Pat. Nos. 2,972,948 and 3,661,086, shaped charge warheads have been disclosed in which a forward facing cavity with a liner of suitable material is employed to enhance the armor piercing effectiveness of a given quantity of explosive. The explosive collapses the liner and projects particles thereof forward in a sharply focused hypervelocity jet having greatly enhanced armor piercing capability.
A number of factors are believed by the applicant to be influential in producing and controlling such a jet and thereby affecting its effectiveness. Such factors may include along or in combination the shape and type of explosive, the presence, location, material and geometry of a wave shaper in the explosive material, the material, thickness and shape of a casing containing the explosive, and the shape, axial variation of thickness and material in the liner.
The selection of specific values for the above factors depends upon the characteristics desired in the jet, such as, for example, the velocity at the front and rear of the jet, its diameter, distribution of velocity along its length and the time required for the jet to break up from a continuous state into a series of axially aligned particles. However, it is not always possible to optimally combine all of the above parameters to produce a jet having the desired characteristics. In addition, many of the parameters are limited by practical considerations such as availability and cost of materials, the ability and/or cost to fabricate a specific design and the total weight and/or length of the shaped charge warhead.
In addition, it may be desirable to modify the characteristics of the jet of an existing shaped charge warhead so that additional types of targets can be engaged with the same weapon system. In order to modify the jet characteristics using the above-named parameters, substantial modification of the shaped charge warhead is required, usually including removal of the explosive from the warhead. Such removal is extremely dangerous and greatly restricts the number of facilities which are capable of doing such retrofitting.